Standardized questionnaire that inquired about reproductive and medical history, smoking history, oral contraceptive use, and the following questions related to weight and weight history: weight at age 18, 30, 40, and current weight and height.

No significant associations were observed between weight status/weight change variables and ovarian cancer risk. No significant differences were observed between cases and controls for the following weight status/weight change variables: height, current weight, weight at ages 18, 30, and 40; changes in weight from ages 18–30, 30–40, 18–40; and BMI at ages 18, 30, and 40*.*Data adjusted for age at menarche, parity, oral contraceptive use, height, and history of hormone replacement therapy

Questionnaire of self-reported height and weight to calculate observed BMI at date of questionnaire and during young adulthood Included Mendelian Randomization approach: Calculated weighted genetic score for BMI and height (see paper for details)

Standardized questionnaire including questions related to family and personal history of cancer, medical and reproductive history, and the following questions related to alcohol consumption: Current consumption, age at first and last use, average number of drinks per week, type of alcohol consumed.Baseline questionnaire completed at time of clinic appointment and follow-up questionnaires completed every 2 years thereafter

259 incident cases observed.Significant relationships were not observed between breast cancer risk and the following alcohol variables in adjusted models*: ever use of alcohol, cumulative consumption, age at first use, alcohol use by the first full-term birth.Significant relationships were not observed between ever or current use of alcohol and breast cancer risk by menopausal status, pathogenic gene variant, and age of breast cancer diagnosis among cases.*Data adjusted for age at baseline, BRCA1/2 pathogenic germline gene variant, age at menarche, oral contraceptive use, history of breast feeding, mean parity, oophorectomy status, and country of residence.

Case-Control, data from French National BRCA 1/2 Carrier Cohort (GENEPSO)

Dietary habits- alcohol

Standardized questionnaire administered by mail inquiring about reproductive factors, tobacco use, alcohol consumption at age 20, and history of chest x-ray exposure

Among women withBRCA1pathogenic germline gene variant*:- When alcohol use was stratified by tobacco use (ever vs never smoker) there were no significant interactions observed (p > 0.05).-When tobacco use was stratified by alcohol use (ever vs never use of alcohol) the only significant interactions observed were among women who reported never drinking alcohol.Among women withBRCA2pathogenic germline gene variant*:Ever use--No: 1.00--Yes: HR, 1.21 (0.68,2.15)Consumed > 5 glasses per week at age 20--No: 1.00--Yes: HR, 1.78 (0.97,3.27)-There were no significant interactions between alcohol and tobacco use (p = 0.75). Therefore, analysis for tobacco and alcohol use were not stratified among women with BRCA2 pathogenic germline gene variants as it was for women with BRCA1 pathogenic germline gene variant.*Data adjusted for parity, menopausal status, gene, smoking history, number of years of smoking interruption

Case-Control, data from six research institutions in USA, Canada, and Australia who were part of Breast Cancer Family Registry, and both the Kathleen Cuningham Foundation Consortium for Research into Familial Breast Cancer in Australia, and the Ontario Cancer Genetics Network in Canada

Case-Only, data from the Genetic and Environmental Modifiers of BRCA 1 and BRCA 2 pathogenic germline gene variants Study (GEMS) Cases were identified either prospectively or retrospectively pending on which center was collecting data

Dietary habits- alcoholWeight status

Risk factor questionnaire that inquired about demographic information, medical and reproductive history, use of oral contraceptives, smoking status, alcohol use, and weight historyProspective enrollment of breast cancer cases used either the GEMS questionnaire or included a supplement to a pre-existing questionnaire to capture lifestyle data not included in the original questionnaire but included in the GEMS questionnaireRetrospective enrollment of breast cancer cases used a similar risk factor questionnaire but not the specific GEMS questionnaire

845 matched case-control pairs652 pairs with BRCA1193 pairs with BRCA2Cases were diagnosed with breast cancer as their first or only cancer

Case-Control, data from 40 centers in 4 countries

Dietary habits- coffee

Standardized questionnaire that inquired about demographic information, ethnicity, parity, family history, reproductive and medical history, use of oral contraceptives, smoking history, alcohol consumption and coffee consumption.-questions related to caffeinated and decaffeinated coffee consumption include: ever use, current use, age when started drinking coffee, age when stopped drinking coffee, average daily coffee consumption7.8 years on average elapsed from diagnosis date to questionnaire administration

Validated food frequency questionnaire developed by the National Cancer Institute of Canada. The questionnaire covered the 1-year period prior to diagnosis for cases and the corresponding time period for controls. Included dietary habits, multivitamins, supplements and alcohol use.Assessed dietary intake via the following diet-quality indexes:-Alternative healthy eating index (AHEI)-Diet quality index-revised (DQI-R)-alternate Mediterranean diet index (aMED)-Canadian healthy eating index (CHEI)Also included general lifestyle questionnaire to collect baseline data on other lifestyle variables.Logistic regression analysis was only conducted on diet quality variables.

Open-ended questionnaire collecting the following information about each supplement taken since age 18:-type of supplement-brand name of supplement-weekly frequency of supplement use-supplement dose-duration of use

Validated semi-quantitative food frequency questionnaire that covered the 1-year period prior to diagnosis for cases and the corresponding time period for controlsLifestyle core questionnaire for physical activity, weight change, and other lifestyle factors such as smoking history, menopausal status, oral contraceptive use, medical and reproductive historyPhysical activity information covered the 2-year period before diagnosis or interview for controlsWeight history information included height, current weight, weight at age 18 and 30.

Standardized questionnaire that inquired about demographic information, ethnicity, parity, family history, reproductive and medical history, use of oral contraceptives, smoking history, weight at birth, age 18, 30 and 40, current weight and height8.8 years on average elapsed from diagnosis date to questionnaire administration

Standardized risk factor questionnaireQuestions related to body weight/weight change include weight at age 18, current weight and current height, body weight in different age periods (10-year increments starting at age 20 up to 70+)Specifically assessed weight change in relation to menopausal status

Significant associations were not observed among the following variables in relation to premenopausal breast cancer risk among women with BRCA 1/2 pathogenic germline gene variants: body weight at age 18, BMI at age 18, current body weight, current BMI, adult weight change, and relative weight change*,**.Current weight (kg) and postmenopausal breast cancer risk*,***:< 72: 1.00≥72: HR, 2.10 (1.23,3.59)-No other significant associations observed for weight change variables and postmenopausal breast cancer risk.*Data analyzed as time-varying Cox-proportional hazards model, stratified by gene and birth cohort, clustered for family, and adjusted for parity, type of menopause and history of hormone replacement therapy, and lifetime sports activity.**Results observed were the same for weighted cohort approach analysis and unweighted analysis.***Results are for unweighted analysis, underpowered to conduct weighted cohort approach analysis.

Questionnaire of self-reported height and weight to calculate observed BMI at date of questionnaire and during young adulthoodIncluded Mendelian Randomization approach: Calculated weighted genetic score for BMI and height (see paper for details)

Retrospective cohort of Ashkenazi Jewish women, data from 12 participating cancer centers in the greater New York City area

Weight statusPhysical activity

Data collection method not provided in detailWeight status was inquired at menarche and age 21Physical activity behavior was inquired during adolescence

Normal weight status (per BMI) at menarche (p = 0.017) and age 21 (p = 0.021) was associated with breast cancer onset at an older age*.Engagement in physical activity as a teenager was associated with breast cancer onset at an older age (p = 0.034)*.*Data adjusted for decade of birth of the proband.

Standardized risk factor questionnaireQuestions related to physical activity behavior include: type of sport, number of hours spent per week, ages at which it was practiced. Questions were specific to activities performed for at least 6 months for at least 1 h/week.